Referring to FIGS. 1-4, coach or motor home frames or chassis, such as frame 100, typically have a pair of frame rails, such as frame rails 108, 110, and a front and rear suspension assembly, such as front suspension assembly 120 and rear suspension assembly 130, mounted to each frame rail. Front and rear suspension assemblies 120, 130 each include one or more mounts or brackets coupled to an associated frame rail, one or more movable suspension arms coupled to the mount or mounts, and one or more vibration dampening devices, such as shock absorption and/or piston-type air springs.
For example, front suspension assembly 120 includes a pair of brackets 122 (FIG. 3) each secured to frame rail 110, it being exemplary of frame rail 108, suspension arms 124 coupled to a respective bracket and front axle (not shown), an air spring 126, and a shock absorber (see FIG. 1).
Overview
With reference to FIG. 3, each rear suspension assembly, with rear suspension assembly 130 being exemplary of such assemblies, comprises a mount, e.g., spring hanger bracket 132 and axle support bracket 134, mounted to frame rail 110. The spring hanger bracket 132 and to the axle support bracket 134 are fixed relative to each other. The rear suspension assembly 130 includes a suspension arm, or beam, 136 coupled to the spring hanger bracket 132 at a front end and the axle support bracket 134 at an opposite rear end. The suspension arm 136 is movable, e.g., pivotable, relative to the spring hanger bracket 132. The rear suspension assembly 130 also includes an air spring 138 and a shock absorber 140 mounted to the frame rail 110 at a first ends and a rear axle assembly 139 (FIG. 1), which includes rear wheels 141. The rear axle assembly 139 is movable relative to the spring hanger bracket 132 (FIG. 3) and axle support bracket 134 such that as the wheels travel over uneven surfaces, the air springs and shock absorbers expand and contract to dampen the vibrational effects caused by travel over such surfaces.
The expansion and contraction of the vibration dampening devices allows the suspension arm 136 to pivot about attachment point 142. The components of the rear suspension assembly 130 can be selected and calibrated to provide desirable vibration dampening characteristics. For example, the length of the spring hanger bracket 132 and the location of the attachment points 142 can be predetermined to provide desirable and specific vibration dampening characteristics. As one example, the length X (FIG. 7) of the spring hanger from the bottom of the lower frame rail to the beam pivot at 142 can be 11.35 inches, and the lengths Y and Z from the bottom of the frame rail to connection points for the tensioning member can, for example, respectively, be 8.51 inches and 11.51 inches. These dimensions can be varied.
Although not particularly shown, most motor homes or coaches include one or more storage compartments located below the frame rails and between the front and rear assemblies. The storage compartments can be used for storing any of various items, such as, for example, luggage, electrical equipment, generators and water pumps.
Typically, storage compartments are supported by at least two tension members, such as tension member 150 (FIGS. 1-4), each mounted to one of the two frame rails, such as frame rail 110, in a spaced apart manner relative to each other and the frame rails such that the compartments occupy a space 153 (FIG. 2) defined generally between the frame rails and tension members (see FIG. 3). Tension member 150 can be any of various elongate members configured to support a predetermined weight. For example, in some implementations, tension member 150 includes a bar 151, such as a hollow or solid bar, having any of various cross-sectional shapes, such as circular or rectangular, and be made of any of various strong and durable materials, such as a steel alloy.
With conventional motor home frames, the front ends of each of the tension members are mounted in a spaced apart relationship relative to the frame rails via front and rear mounting brackets attached directly to the frame rails and extending downwardly generally transversely from the frame rails. For example, each frame rail includes a front mounting bracket, such as front mounting bracket 160 positioned nearer the front wheel assembly and a rear mounting bracket (not shown) similar to mounting bracket 160 positioned nearer, but forwardly of, the rear suspension assembly. A front end of each tension member is attached to a respective front mounting bracket and a rear end of each tension member is attached to a respective rear mounting bracket. In conventional coach chassis, both the front and rear tension member mounting brackets are mounted to the frame rails independent of the front and rear suspension assemblies.
The weight of the various items stored in the storage compartments places the tension members in tension and urges the ends of the tension members inwardly toward each other. The greater the overall weight of the items, the greater the inward draw of the ends of the tension members on the mounting brackets. Accordingly, the tension members are mounted to mounting brackets independent of the front and rear suspension assemblies so that the tensioning of the tension member does not affect the calibration of the suspension assemblies.